Commit Message

Currently device hotplug removal code is tied to device removal via
ACPI. All pci devices that are removable via device_del() require the
guest to respond to the request. In some cases the guest may not
respond leaving the device still accessible to the guest. The management
layer doesn't currently have a reliable way to revoke access to host
resource in the presence of an uncooperative guest.
This patch implements a new monitor command, drive_del, which
provides an explicit command to revoke access to a host block device.
drive_del first quiesces the block device (qemu_aio_flush;
bdrv_flush() and bdrv_close()). This prevents further IO from being
submitted against the host device. Finally, drive_del cleans up
pointers between the drive object (host resource) and the device
object (guest resource).
Signed-off-by: Ryan Harper <ryanh@us.ibm.com>
---
blockdev.c | 39 +++++++++++++++++++++++++++++++++++++++
blockdev.h | 1 +
hmp-commands.hx | 18 ++++++++++++++++++
3 files changed, 58 insertions(+), 0 deletions(-)